srx70024
New member
Gentlemen,
I'm having a small issue with my 1980 srx 440 only pumping fuel into one of the fuel lines. The generator side carb is getting a nice flow of fuel, but the clutch side only seems to trickle. I put all new fuel lines and vacuum line on with zip ties, cleaned the carbs and a new fuel filter before the fuel pump. I just took the pump off and took it apart and I found what looked to be the remains of a bug in the pump. It was stuck in the area of those two small round clear plastic diaphrams, but it wasn't big enough to plug any of the fuel ports. None of the ports were plugged and the pump looks fairly new. The pump diaphrams all look good with no rips or tears. It's a stock Mikuni pump with the two fuel output lines coming off the same section/block.
I bought the sled a few months back and this is the first time I've had a chance to really run it. When I got it running after I cleaned the carbs, it ran real strong. I rode it around for a little while and it started to bog a little. I shut if off and checked the lines and that is when I noticed this problem.
I ordered a new fuel pump and will have it on this weekend, but this really has my curiousity. I've worked on a lot of sleds in the past, but never with a problem like this.
Any ideas?
Thanks all.
I'm having a small issue with my 1980 srx 440 only pumping fuel into one of the fuel lines. The generator side carb is getting a nice flow of fuel, but the clutch side only seems to trickle. I put all new fuel lines and vacuum line on with zip ties, cleaned the carbs and a new fuel filter before the fuel pump. I just took the pump off and took it apart and I found what looked to be the remains of a bug in the pump. It was stuck in the area of those two small round clear plastic diaphrams, but it wasn't big enough to plug any of the fuel ports. None of the ports were plugged and the pump looks fairly new. The pump diaphrams all look good with no rips or tears. It's a stock Mikuni pump with the two fuel output lines coming off the same section/block.
I bought the sled a few months back and this is the first time I've had a chance to really run it. When I got it running after I cleaned the carbs, it ran real strong. I rode it around for a little while and it started to bog a little. I shut if off and checked the lines and that is when I noticed this problem.
I ordered a new fuel pump and will have it on this weekend, but this really has my curiousity. I've worked on a lot of sleds in the past, but never with a problem like this.
Any ideas?
Thanks all.
YAMMIEGOD3:16
Active member
TRY THE NEW FUEL PUMP, BUT POSSIBLEY YOU HAVE BAD CRANK SEAL. HARD TO TROUBLE SHOOT THIS. 3:16 (yammie tony)
srx70024
New member
Thanks Tony. We'll see what happens this weekend.
since it ur clutch side, spray a tiny amount of starting fluid behind ur clutch when the engine is running. if the cylinder fires or the rpms jump, u have a bad crank seal.
did you replace the fuel filter in the tank. seems like this is falling apart and getting in the pump...
These posts arent addressing the reason for only one fuel line working properly. There is only one vacumn line running the pump, correct? So if one line is working the other should also. I think! Check the carb that is not getting good fuel flow, if it is plugged, it may be restricting the amount of fuel the pump can push through it. ( or are you checking the flow with the lines off the carbs? )
srx70024
New member
No, I did not replace the filter in the tank. I did put the inline filter before the pump though.
Yes, one line runs the pump.
Yes, one line runs the pump.
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srx70024
New member
I put the new fuel pump on and it looks like it cured the fuel flow problem, but I think there is also a seal problem. It only runs with the choke on. As soon as I take the choke off it dies. The carbs have been off and were clean.
I can't keep it running long enough to try spraying the starting fluid at the seal behind the clutch.
Time to yank the engine. Any suggestions while I have it out and apart?
Thanks.
I can't keep it running long enough to try spraying the starting fluid at the seal behind the clutch.
Time to yank the engine. Any suggestions while I have it out and apart?
Thanks.
Shafner79
New member
I have an 89 Ovation 340 and when I first got it I had the same problem. I first thought it was ignition related because the 1 cylinder would not fire. I changed coils, cleaned carbs changed pump, checked for leaks in the lines, cleaned the tank......finally I gave up and sent it to yamaha....$500.00 later I had new crank seals and it has run awesome ever since!
srx70024
New member
Just an update...
Big-Kid was right, it was the fuel filter in the tank. It was falling apart and getting sucked up into the pickup tube cutting off fuel supply.
It runs like a champ now and it goes like hell!!!!
Thanks everyone for your input.
Happy New Years.
Big-Kid was right, it was the fuel filter in the tank. It was falling apart and getting sucked up into the pickup tube cutting off fuel supply.
It runs like a champ now and it goes like hell!!!!
Thanks everyone for your input.
Happy New Years.